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Ultrasonically Extracted Flaxseed Mucilage: An Effective EGG Substitute in Gluten-Free Noodles to Enhance Cooking Quality and Reduce Energy Value
No full textYaver, Elif/0000-0002-2651-9922BACKGROUND Flaxseed mucilage is a natural hydrocolloid that can be easily extracted from whole flaxseed or defatted flaxseed meal. It can be used as a thickening, emulsifying, water-retention, suspending and gelling agent to improve the technological features of foodstuffs. Moreover, flaxseed mucilage, as a natural soluble fiber source, has potential health benefits such as regulating gut microbiota, promoting satiety and reducing cholesterol levels. Due to its technological properties and health benefits, it has recently received attention from consumers, producers and researchers. In this study, flaxseed mucilage was extracted from cold-pressed flaxseed meal using conventional and ultrasound-assisted extraction methods. To enhance nutritional quality, solutions of conventionally and ultrasonically extracted flaxseed mucilages were separately used in gluten-free noodles as egg substitutes at 0%, 25%, 50%, 75% and 100% levels. The effects of mucilage type and level on the chemical, technological, textural and sensory quality of noodles were investigated.RESULTS Incorporation of sonicated mucilage revealed a firmer texture, lower cooking loss and stronger antioxidant activity in gluten-free noodles compared with conventionally extracted mucilage. Increasing the level of flaxseed mucilage from 0 to 100% reduced fat content and energy value, and enhanced the antioxidant activity of noodles. Substitution of eggs with mucilage (up to 75%) exhibited better cooking quality than 100% egg noodles. Sensorially, the substitution of eggs with sonicated mucilage elicited greater overall acceptability scores.CONCLUSION The results demonstrated that ultrasonically extracted flaxseed mucilage has potential as a natural and sustainable hydrocolloid to replace eggs in the preparation of high-quality and healthy gluten-free noodles. (c) 2025 Society of Chemical Industry.This work was supported by Konya Technical University, Unit of Scientific Research Projects (grant number 232022043).Konya Technical University, Unit of Scientific Research Projects [232022043
Analysis of Aga Khan Awards for Architecture in the Context of Spatial Identity-Natural Light Interaction
No full textNatural light, which plays an important role in making the space perceptible, visible and functional, not only fulfils a physical need, but also gives aesthetic, symbolic and emotional meanings to the space. Natural light, which adds spirit and depth to the space, enriches the architectural experience by coming to the fore as a tool that makes you feel the flow of time. Natural light, which forms the identity of the space with this multi-layered effect, is an important phenomenon that reflects the unique character of the building, the emotional bond it establishes with the user and the cultural context in which it is located. This study aims to determine which role of natural light is more effective in creating spatial identity by analysing the relationship between spatial identity and natural light through projects that have received the Aga Khan Architecture Award since 1977, which effectively incorporate many site-specific elements from the use of local materials to natural light into the design. In this context, firstly, the concepts of 'spatial identity', 'natural light', and 'Aga Khan Award for Architecture' and their relations with each other are discussed at the conceptual level. Within the scope of the study, by analysing the literature, the roles of natural light in creating spatial identity were determined as 12 criteria under 4 main headings as functional, semantic, aesthetic and psychological roles. In the field study, a total of 15 buildings were selected, including one public building that received an award from each cycle, starting from the first award cycle of 1978-1980 until the last award cycle of 2020-2022. The jury reports of the buildings were read, interior and exterior photographs, plans and all kinds of printed and digital sources showing their interaction with natural light were used, and the projects were analysed spatially and contextually. While the buildings were examined through the parameters determined within the scope of the thesis, each structure was classified into three groups as 'effective', 'partially effective' and 'ineffective' in line with meeting the criteria in the analysis table. During the analyses, the buildings were evaluated as 'effective' if they met all or most of these criteria, 'partially effective' if they met half or almost half of them, and 'ineffective' if they did not meet any of them. Within the scope of the study, it has been determined that the semantic aspect of natural light is dominant on spatial identity and is an effective factor in the award of the buildings Criteria reflecting the semantic effect of natural light on spatial identity: 'establishing a relationship with the architectural concept', 'highlighting elements with sacred, cultural, historical or symbolic meaning', 'providing spatial organisation'; the projects that successfully interpreted these criteria and transferred them to the design were found successful by the jury. In line with the data obtained in the study, it was seen that qualified spaces were created in the designs made by considering the effect of natural light on spatial identity. As a result, it is thought that this study provides designers with a valuable perspective on the importance of natural light in reflecting the unique character of the building.Mekânın algılanabilir, görülebilir ve işlevsel hâle gelmesinde önemli bir rol üstlenen doğal ışık, yalnızca fiziksel bir gereksinimi karşılamakla kalmayıp aynı zamanda mekâna estetik, sembolik ve duygusal anlamlar kazandırmaktadır. Mekâna ruh ve derinlik katan doğal ışık, zamanın akışını hissettiren bir araç olarak ön plana çıkarak mimari deneyimi zenginleştirmektedir. Bu çok katmanlı etkisiyle mekânın kimliğini oluşturan doğal ışık; yapının özgün karakterini, kullanıcıyla kurduğu duygusal bağı ve içinde yer aldığı kültürel bağlamı yansıtan önemli bir olgudur. Bu çalışma, 1977 yılından günümüze yerel malzeme kullanımından doğal ışığa kadar yere özgü birçok unsurun etkili bir şekilde tasarıma dâhil eden Ağa Han Mimarlık Ödülü almış projeler üzerinden mekânsal kimlik-doğal ışık ilişkisini analiz ederek; mekânsal kimlik oluşturmada doğal ışığın hangi rolünün daha etkili olduğunun tespitini amaçlamaktadır. Bu bağlamda öncelikle 'mekânsal kimlik', 'doğal ışık' ve 'Ağa Han Mimarlık Ödülü' kavramları ve birbirileri ile ilişkileri kavramsal düzeyde ele alınmıştır. Çalışma kapsamında, literatür analiz ve sentez edilerek doğal ışığın mekânsal kimlik oluşturmadaki rolleri; işlevsel, anlamsal, estetik ve psikolojik roller olarak 4 ana başlık altında 12 ölçüt olarak belirlenmiştir. Alan çalışmasında ise 1978-1980 yılı ilk ödül döngüsünden başlayarak 2020-2022 yılı son ödül döngüsüne kadar olan her döngüden ödül almış bir kamusal yapı olmak üzere toplam 15 adet yapı seçilmiş, restorasyon ve koruma projeleri çalışma alanı kapsamı dışında tutulmuştur. Yapıların jüri raporları okunarak, iç ve dış mekân fotoğrafları, planları ve doğal ışıkla etkileşimlerini gösteren her türlü basılı ve dijital kaynaktan yararlanılmış olup projeler mekânsal ve bağlamsal olarak incelenmiştir. Yapılar tez kapsamında belirlenen parametreler aracılığıyla incelenirken, her yapı analiz tablosundaki ölçütleri sağlama doğrultusunda, 'etkili', 'kısmen etkili' ve 'etkisiz' olmak üzere üç grupta sınıflandırılmıştır. Analizler gerçekleştirilirken yapılar bu ölçütlerin hepsini veya çoğunluğunu sağlıyorsa 'etkili', yarısını veya yarısına yakın bir oranı sağlıyorsa 'kısmen etkili', hiçbirini sağlamıyorsa 'etkisiz' olarak değerlendirilmiştir. Çalışma kapsamında yapıların doğal ışık kullanımına ilişkin genel bir değerlendirme oluşturulmuş; doğal ışığın anlamsal yönün mekânsal kimlik üzerine baskın olduğu ve yapıların ödül almasında etkili bir unsur olduğu belirlenmiştir. Doğal ışığın mekânsal kimlik üzerine anlamsal etkisini yansıtan ölçütler; 'mimari konseptle ilişki kurma', 'kutsal, kültürel, tarihi veya sembolik anlam taşıyan ögeleri vurgulama', 'mekânsal organizasyon sağlama' olmak üzere, bu ölçütleri başarılı bir şekilde yorumlayıp tasarıma aktaran projelerin jüri tarafından başarılı bulunduğu tespit edilmiştir. Çalışmada elde edilen veriler doğrultusunda, doğal ışığın mekânsal kimlik üzerindeki etkisi göz önünde bulundurularak yapılan tasarımlarda nitelikli mekânlar oluşturulduğu görülmüştür. Sonuç olarak bu çalışmanın doğal ışığın, yapının özgün karakterini yansıtmadaki önemi konusunda tasarımcılara değerli bir bakış açısı sağlayacağı düşünülmektedir
DSTATCOM Tabanlı KUAG Sistemlerinde Gerilim Regülasyonu için DQ ve CSD Yöntemlerinin Karşılaştırmalı Çalışması
No full textKendinden Uyarımlı Asenkron Generatör (KUAG), bağımsız güç üretim sistemlerinde, önemli bir rol oynamaktadır. SEIG'ler yük koşulları değiştiğinde terminal gerilimini korumakta zorluk çektiği için etkili bir kompanzasyon ve kontrol sistemine ihtiyaç duyulmaktadır. Dağıtım Statik Kompanzatörleri (DSTATCOM) hızlı dinamik tepkileri, reaktif güç desteği ve harmonik azaltma yetenekleri ile ön plana çıkmaktadır. DSTATCOM'ların performansı kontrol yönteminin etkinliğine bağlıdır. Bu çalışmada, yaygın olarak kullanılan dq yöntemi ile Akım Senkron Algılama (CSD) yönteminin performansı doğrusal olmayan yükler, dengesiz yükler ve DC ofset koşulları altında karşılaştırılmıştır. CSD yöntemi, PCC gerilimlerini filtrelemedeki etkinliği, tepe değerini tahmin etmesi ve basit algoritması ile öne çıkmaktadır. Ayrıca akım ve gerilimlerde meydana gelen DC ofset durumlarında faz gerilimi kestirimi daha üstündür. dq yönteminde ise faz senkronizasyonundaki yüksek doğruluk ve kararlılığı sayesinde harmonik bastırma, akım ve gerilim dengeleme ve DC ofset etkilerini azaltmada başarılı performans sağlamıştır. Her iki yöntemde de IEEE-519 standartlarına uygun şekilde SEIG akım ve geriliminin toplam harmonik distorsiyonu (THD) %5'in altındadır
Impacts of Dye-Contaminated Effluents on the Environment
No full textSynthetic dyes employed in sectors such as textile, printing, paper, and leather result in substantial water contamination. Discharging untreated industrial effluent into the environment poses a substantial risk to organisms. The presence of industrial dyes in natural environments poses a risk of contamination, potentially impacting the suitability of these habitats for various organisms. Textile dyes have significant negative impacts, such as becoming part of the food chain, disrupting photosynthesis, retarding, or completely stopping the growth of plants, as well as causing cancer and toxicity issues. Nevertheless, it is entirely possible to convert and mineralize textile dyes. At this juncture, it is imperative to treat wastewater that contains dyes efficiently, using eco-friendly methods to curb their detrimental impact on the environment and the natural aquatic resources. This book chapter will scrutinize all aspects of the different methods of industrial dye removal and compare the latest technologies commonly used for this purpose. © 2025 Elsevier B.V., All rights reserved
Assessing the Vulnerability of Cities to Climate Change: A New Index Proposal for Türkiye Cities
No full textOn a global scale, as cities continue to grow and climate change brings increasing hazards, the vulnerability and risk levels for cities are also rising. Assessing the risk and vulnerability of urban areas has become more vital now than in previous decades. In this context, the climate–adaptive city approach is gaining importance alongside sustainable development. Türkiye’s geographical location is considered one of the most vulnerable regions in terms of climate change, due to decreasing precipitation and rising temperatures. In the literature, some studies primarily evaluate the full range of risks associated with climate change, while others develop a climate–adaptive city approach that focuses on a single risk. However, the consequences of climate change vary across regions and countries. In this study, the vulnerability of cities to climate change is discussed separately for each risk. Vulnerability criteria are considered separately for drought, sea-level rise, heavy rainfall, and extreme heat. For each risk, indicators of the impact, pressure, vulnerability, resistance, and adaptive capacity that contribute to the risk are identified. Methodologically, relevant studies in the literature were compiled, previous studies were utilized in determining the indicator, and new indicators were developed. As a result, a holistic approach has been developed to assess the vulnerability of cities to climate change across all risks. This makes it possible to identify both how cities remain unprepared for the consequences and risks of climate change and, on the other hand, the climate–adaptive aspects of cities. This study is intended to contribute to researchers working on urban resilience as well as to urban municipalities. In conclusion, a guiding index has been put forward to inform planning and decision-making processes for the creation of a climate–adaptive city
Fractal Characterization of Crack Patterns in Intact Rocks Under Triaxial Compression
No full textUnderstanding crack development in rocks under varying confining stresses is critical for assessing rock mass stability in engineering projects, such as tunnels, slopes, and underground storage facilities. This study employs fractal dimension (D) analysis to quantify crack complexity in diabase, ignimbrite, and marble subjected to triaxial compression, with implications for predicting environmental impacts of rock failure. Crack patterns were evaluated using digital image processing and the box-counting method. Results demonstrate that both confining stress and mineralogical composition significantly influence crack morphology and failure modes. Diabase exhibits highly branched cracks (higher D values) due to its interlocking grain texture, while marble produces simpler cracks (lower D values). The cracking behavior of ignimbrite lies between that of marble and diabase, characterized by curved cracks influenced by its weak matrix. Increasing confinement reduces D values, reflecting smoother cracks and transitions from tensile to shear-dominated failure. These findings highlight the utility of fractal analysis in geomechanics, offering quantitative insights into stress-induced damage evolution and its relevance to sustainable engineering applications.Turkiye Bilimsel ve Teknolojik Arastirma KurumuThe authors thank Prof. Kamil Kayabal ; imath; for providing the rock blocks, Deniz Y ; imath;lmaz for conducting the laboratory tests with precision, and Prof. Kayhan Develi for his contributions to the interpretation of the fractal analysis results
Investigation of the Effect of Organic-Based Colemanite Compound on the Performance Properties of Bitumen and Bituminous Mixtures
No full textIn this thesis study, pure bitumen with a penetration grade of 50/70, supplied from Tüpraş Kırıkkale Refinery, was used as the primary binder. In the laboratory, a new additive was chemically synthesized using colemanite and monoethylene glycol, and this compound was named the 'Organic Based Colemanite Compound (OEKB).' The OEKB was used as an additive for bitumen modification. During the modification process, OEKB was added to the bitumen in proportions of 1%, 2%, 3%, 5%, and 8% by weight. The modification was carried out at 150 °C for 20 minutes using a mechanical stirrer. Various tests based on both conventional and Superpave methods were conducted on the bitumen samples modified with OEKB. The conventional test methods included the viscosity test, penetration test, softening point test, force-ductility test, and elastic recovery test. As part of the Superpave performance tests, the Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR), Rolling Thin Film Oven Test (RTFOT), and Pressure Aging Vessel (PAV) tests were performed. Additionally, bituminous mixtures prepared with the modified binders were subjected to the Marshall mix design, indirect tensile strength test, and Nicholson stripping test. As a result of the experiments, it was confirmed through penetration and softening point test results that the consistency of the bitumen increased when modified with OEKB compared to the pure bitumen. According to the viscosity test data, it was observed that the additive decreased the consistency of the bitumen at high temperatures. DSR test results indicated a significant improvement in rutting resistance of the modified bitumen, while the BBR test results demonstrated enhanced low-temperature performance. The addition of 2% OEKB to bitumen has enabled the development of high and low performance grades to a higher advanced level. In the Marshall mix design test, an increase in the stability of the mixture was observed due to the use of the additive. In the indirect tensile strength test performed at different temperatures, a notable increase was particularly observed at 40°C as 8.8%. Finally, the results of the Nicholson stripping test showed that the stripping resistance of the bituminous mixtures was improved significantly from 60 % to 80 % with the use of OEKB.Bu tez çalışmasında temel bağlayıcı olarak, 50/70 penetrasyon derecesine sahip Tüpraş Kırıkkale Rafinerisi'nden temin edilen saf bitüm kullanılmıştır. Laboratuvar ortamında, kolemanit ve monoetilen glikol kullanılarak tarafımızca kimyasal sentezi gerçekleştirilen yeni bir katkı maddesi geliştirilmiş ve bu bileşik 'Organik Esaslı Kolemanit Bileşiği (OEKB)' olarak adlandırılmıştır. OEKB, bitümün modifikasyonunda katkı maddesi olarak kullanılmıştır. Bitüm modifikasyonu sürecinde OEKB, bitüme ağırlıkça %1, %2, %3, %5 ve %8 oranlarında ilave edilmiştir. Modifikasyon işlemi, 150°C sıcaklıkta, 20 dakika boyunca mekanik karıştırıcı yardımıyla gerçekleştirilmiştir. Modifiye edilen bitüm numunelerine, hem geleneksel hem de Superpave yöntemlerine dayalı çeşitli deneyler uygulanmıştır. Geleneksel deney yöntemleri arasında viskozite testi, penetrasyon testi, yumuşama noktası testi, kuvvet ölçümlü düktilite deneyi ve elastik geri dönme deneyi yer almaktadır. Superpave performans deneyleri kapsamında ise Dinamik Kayma Reometresi (DSR), Kiriş Eğme Reometresi (BBR), Dönel İnce Film Isıtma Kaybı Testi (RTFOT) ve Basınçlı Yaşlandırma Kabı (PAV) testleri uygulanmıştır. Ayrıca, modifiye bitüm kullanılarak hazırlanan bitümlü karışımlar üzerinde Marshall karışım tasarımı, indirekt çekme mukavemeti ve Nicholson soyulma testleri gerçekleştirilmiştir. Yapılan deneyler sonucunda, OEKB katkısı ile modifiye edilen bitümün saf bitüme kıyasla kıvamının arttığı, penetrasyon testi ve yumuşama noktası testi sonuçları ile doğrulanmıştır. Viskozite deneyi verilerine göre, katkı maddesinin yüksek sıcaklıklarda bitümün kıvamını azalttığı gözlemlenmiştir. DSR testi sonuçları, modifiye bitümün tekerlek izi direncinde önemli bir artış sağladığını ortaya koyarken; BBR testi, düşük sıcaklık performansında iyileşme olduğunu göstermiştir. Bitüme %2 OEKB eklenmesi, yüksek ve düşük performans sınıflarının daha ileri seviyeye geliştirilmesine olanak sağlamıştır. Marshall tasarımı deneyinde, katkı maddesi sayesinde karışımın stabilitesinde artış gözlemlenmiştir. Farklı sıcaklıklarda gerçekleştirilen dolaylı çekme mukavemeti deneyinde özellikle 40°C'de % 8,83 seviyesinde belirgin bir artış tespit edilmiştir. Son olarak, Nicholson soyulma test sonuçları, OEKB katkısı ile hazırlanan bitümlü karışımların soyulma direncinde % 60'tan % 80'e artış sağladığını göstermiştir
Preparation and Evaluation of Nicotine and Quercetin Loaded Polyvinyl Alcohol Nanofiber Wound Dressings
No full textThe skin, which is a protective barrier for the human body, can be injured from time to time as a result of disease or trauma. Electrospun nanofiber wound dressings made from biopolymers for skin regeneration and wound healing have been widely investigated in recent years. This study successfully prepared PVA-based nanofiber wound dressings loaded with nicotine and quercetin by the electrospinning method to accelerate wound healing. The nanofibers were characterized morphologically, physically, and chemically, and then their cytotoxicity levels and effects on wound healing were evaluated in vitro. First, three different concentrations of PVA solutions were prepared, and one nanofiber wound dressing was produced with each of them. Next, characterization studies of the nanofiber wound dressings were performed, and the optimal formulation was selected. Morphological examinations by SEM analysis revealed that homogeneous and uniform nanofibers with an average diameter of 122.11 +/- 36.22 nm and no bead formation were successfully produced. The structural properties of the nanofiber wound dressings were evaluated by DSC and FTIR analyses, which revealed that there was no significant physico-chemical interaction between the polymer and the loaded drugs. In terms of drug loading efficiency, the loading efficiency of nicotine was found to be higher compared to quercetin (quercetin: 21.86 +/- 2.1%; nicotine: 99.43 +/- 6.1%), and it was also determined that the nanofiber structure produced increased the solubility of quercetin by approximately two times. The results of MTT assay on L929 cells revealed that the prepared nanofiber wound dressings did not show cytotoxicity, on the contrary, they supported biocompatibility by increasing cell viability. The wound-healing process was evaluated using an in vitro scratch test. The F2 nanofiber wound dressing produced approximately a 3-fold increase in wound closure compared to the control. Studies have shown that nicotine and quercetin-loaded PVA nanofiber dressings have the potential to accelerate wound healing
The Diophantine Equation Ln(k)=(2a-1)(2b-1)
No full textLet k >= 2 be a fixed integer. The k-generalized Lucas sequence {Ln(k)}n >= 0 starts with the positive integer initial values k, 1, 3, ..., 2k-1-1, and each term afterward is the sum of the k consecutive preceding elements. In this paper, we find all solutions of the equation Ln(k)=(2a-1)(2b-1) in integers n >= 2,k >= 2, b >= a >= 0\.The authors thank the referee for comments that improved the quality of our paper. Work by the second author was done while he visited the University of Debrecen in 2024 with a Fellowship from the Hungarian Academy of Sciences. This author thanks the University of Debrecen for excellent working conditions and the Hungarian Academy of Sciences for generous support.Hungarian Academy of Science
Optimizing 3d Guide Vanes To Minimize Secondary Flow and Energy Loss in Turbulent Flow Through a 90-Degree Bend
No full textThe bend is one of the most essential components in a piping system, as it significantly influences the overall flow behavior and system efficiency. Its design and performance directly affect pressure loss, flow separation, and turbulence. Therefore, this study aims to numerically investigate the flow structure around a 90 - degree bend and demonstrate the effectiveness of optimized guide vanes in improving flow characteristics. The numerical analyses were performed by solving the three-dimensional Reynolds-averaged Navier-Stokes (RANS) equations using the SST k - omega turbulence model at Reynolds number Re = 3 x 104 in ANSYS-Fluent. Inserting optimized vanes significantly reduced flow separation, secondary flows, and turbulence, leading to lower energy loss and enhanced system efficiency. The use of optimized guide vanes resulted in several improvements: a noticeable shift in the flow separation point, significantly reduced secondary flow regions, and enhancement in the uniformity of axial velocity. The optimized vanes also broke high-intensity vortex cores into weaker, more stable formations, resulting in reduced turbulence by up to 40%. Pressure distribution was improved, and local resistance was reduced by over 38% with the 3D -OGV configuration. These improvements make the optimized guide vanes a practical and cost-effective solution for engineering applications